1. Field of the Invention
The present invention relates to printing system and printing method for decrypting and printing encrypted image data acquired from a distributor, and an ink tank therefor.
2. Related Background Art
In general, copyrighted images made public on the Internet can be viewed by users who access them. However, to prevent the users from downloading and printing the copyrighted images on printers without paying royalties to creators of the images, i.e., without the creator""s permissions, the copyrighted images made public on the Internet are generally encrypted.
Further, there is a case where a copyrighted image is made public on the Internet without being encrypted. In such a case, whoever accesses the copyrighted image can print the image without paying a royalty to its creator, i.e., without the creator""s permission. Thus, in the case where a copyrighted image is made public on the Internet without being encrypted, each user is given a free hand to pay a royalty for the image to its creator. Therefore, payment of the royalty may not always be made, and there is a possibility that the creator may lose profits he should obtain.
As described above, in a case where a copyrighted image made public on the Internet is encrypted, the encrypted copyrighted image cannot be printed out and used, whereby use of the copyrighted image is restricted. As for such a copyrighted image, users should be permitted to download or print the copyrighted image by paying a royalty so as to remove a restriction on use of the copyrighted image. However, to pay the royalty or permit the users to use the copyrighted image after payment of the royalty, a number of procedures are required between the users and its creator, and a high-speed system taking advantage of a network has heretofore not been established yet.
Under the above circumstances, establishment of a system in which a user acquires permission to use an encrypted copyrighted image by paying a royalty to a creator of the copyrighted image when the user attempts to print the copyrighted image, is desired.
It is an object of the present invention to provide a printing system and a printing method in which a user is permitted to use encrypted copyrighted image data by paying a royalty to a creator of the copyrighted image so as to print the copyrighted image.
A first aspect of the present invention is directed to a printing system constituted by a printing apparatus for printing an image and an external apparatus which is connected to the printing apparatus and has a function of connecting to a network, the system comprising: decryption key storing means for storing a decryption key code to decrypt encrypted image data acquired from a distributor which is connected via the network, and decryption means for decrypting the encrypted image data acquired by the external apparatus from the distributor via the network, by use of the decryption key code, wherein the printing apparatus prints an image in accordance with the image data decrypted by the decryption means.
A second aspect of the present invention is directed to a printing system constituted by a printing apparatus for printing an image and an external apparatus which is connected to the printing apparatus and has a function of connecting to a network. In the system, the external apparatus comprises means for sending to the printing apparatus encrypted image data acquired from a distributor which is connected to the external apparatus via the network, and the encrypted image data contains a first key code to be used for decryption of the image data. The printing apparatus comprises means for storing a second key code which is registered in the distributor and used for decryption of the image data, and decryption key generating means for generating a decryption key code to decrypt the image data from the first key code contained in the encrypted image data acquired by the external apparatus and the second key code. The printing system comprises decryption means for decrypting the encrypted image data acquired by the external apparatus via the network, by using the decryption key code, so as to generate image data which can be printed by the printing apparatus.
A third aspect of the present invention is directed to a printing method in a printing apparatus which is constituted so as to be able to connect to an external apparatus having a function of connecting to a network and prints an image in accordance with image data, the method comprising the steps of: acquiring encrypted image data by the external apparatus from a distributor which is connected to the external apparatus via the network, reading a decryption key code used to decrypt the encrypted image data from the printing apparatus, the decryption key code being data registered in the distributor, decrypting the encrypted image data by use of the decryption key code so as to acquire image data which can be printed by the printing apparatus, and printing an image based on the image data acquired in the decryption step.
A fourth aspect of the present invention is directed to a printing method in a printing apparatus which is constituted so as to be able to connect to an external apparatus having a function of connecting to a network and prints an image in accordance with image data, the method comprising the steps of: acquiring encrypted image data by the external apparatus from a distributor which is connected to the external apparatus via the network, the encrypted image data having a first key code used for decryption, reading a second decryption key code used to decrypt the encrypted image data from the printing apparatus, the second key code being data registered in the distributor, generating a decryption key code to decrypt the encrypted image data from the first key code and the second key code, decrypting the encrypted image data by use of the decryption key code so as to acquire image data which can be printed by the printing apparatus, and printing an image based on the image data acquired in the decryption step.
A fifth aspect of the present invention is directed to an ink tank which is replaceably mounted on an ink jet recording apparatus and which accommodates inks to be fed to an ink jet recording head that is provided in the ink jet recording apparatus and discharges inks, comprising: means for storing a certificate key, decryption key generating means for generating a decryption key code to decrypt encrypted image data sent from the ink jet recording apparatus from a print key attached to the encrypted image data and used to decrypt the encrypted image data and the certificate key, the encrypted image data is image data which has been subjected to an encryption process, and decryption means for decrypting the encrypted image data in accordance with the decryption key code generated by the decryption key generating means, wherein the image data decrypted by the decryption means is recorded by the ink jet recording apparatus.